Não informado. (1949). Agricultural economics research. U.S. Department of Agriculture, Bureau of Agricultural Economics.
Chicagoスタイル(17版)引用形式Não informado. Agricultural Economics Research. Washington: U.S. Department of Agriculture, Bureau of Agricultural Economics, 1949.
MLA(8版)引用形式Não informado. Agricultural Economics Research. U.S. Department of Agriculture, Bureau of Agricultural Economics, 1949.
警告: この引用は必ずしも正確ではありません.